diff --git a/src/index.html b/src/index.html
index 0989be4..02c1fb7 100644
--- a/src/index.html
+++ b/src/index.html
@@ -93,9 +93,11 @@
                     <li><code>&</code> — bitwise AND</li>
                     <li><code>|</code> — bitwise inclusive OR</li>
                     <li><code>^</code> — bitwise exclusive XOR</li>
-                    <li><code><<</code> — left shift</li>
-                    <li><code>>></code> — sign propagating right shift</li>
-                    <li><code>>>></code> — zero-fill right shift</li>
+                    <li><code>~</code> — bitwise NOT</li>
+                    <li><code>&lt;<</code> — left shift</li>
+                    <li><code>&gt;&gt;</code> — sign propagating right shift</li>
+                    <li><code>&gt;&gt;&gt;</code> — zero-fill right shift</li>
+
                 </ul>
                 </p>
             </div>
@@ -136,6 +138,21 @@
     </table>
 </script>
 
+<script data-template="notExpressionView" data-compiled="" type="text/template">
+    <table class="expression">
+        <tr>
+            <td class="label">{m.operand1.input}</td>
+            <td class="bin">{m.operand1Binary}</td>
+            <td class="other">{m.operand1.other}</td>
+        </tr>
+        <tr class="result">
+            <td class="label">{m.sign}{m.operand1.input}={m.result.input}</td>
+            <td class="bin">{m.resultBinary}</td>
+            <td class="other">{m.result.other}</td>
+        </tr>
+    </table>
+</script>
+
 <script data-template="binaryExpressionView" data-compiled="" type="text/template">
     <table class="expression">
         <tr>
diff --git a/src/js/app/bitwise/expression.js b/src/js/app/bitwise/expression.js
index 3722092..f979ce3 100644
--- a/src/js/app/bitwise/expression.js
+++ b/src/js/app/bitwise/expression.js
@@ -3,10 +3,11 @@ app.set('expression', function() {
 
     var exprRegex = /^(-?(?:\d+|0x[\d,a-f]+))\s*(<<|>>|>>>|\||\&|\^)\s*(-?(?:\d+|0x[\d,a-f]+))$/;
     var listRegex = /^(-?(?:\d+|0x[\d,a-f]+)\s?)+$/;
+    var notRex = /^(~)(-?(?:\d+|0x[\d,a-f]+))$/
 
     return {
         canParse: function(string) {
-            return exprRegex.test(string) || listRegex.test(string);
+            return exprRegex.test(string) || listRegex.test(string) || notRex.test(string)
         },
         parse: function(string) {
             var trimmed = string.replace(/^\s+|\s+$/, '');
@@ -14,13 +15,19 @@ app.set('expression', function() {
             var matches = exprRegex.exec(trimmed);
 
             if(matches != null) {
-                return createCalculableExpression(matches);
+                return createTwoOperandExpr(matches);
+            }
+
+            matches = notRex.exec(trimmed);
+            if(matches != null) {
+                return createSingleOperandExpr(matches);
             }
 
             matches = listRegex.exec(string);
             if(matches != null) {
                 return createListOfNumbersExpression(string)
             }
+
         },
         parseOperand: function(input) {
             return new Operand(input);
@@ -28,7 +35,7 @@ app.set('expression', function() {
         createOperand: function(number, kind) {
             var str = number.toString(getBase(kind));
             if(kind == 'hex') {
-                str = "0x" + str;
+                str = toHex(str);
             }
 
             return new Operand(str);
@@ -36,7 +43,7 @@ app.set('expression', function() {
 
     };
 
-    function createCalculableExpression(matches) {
+    function createTwoOperandExpr(matches) {
 
         var m = new app.models.BitwiseOperation();
         m.operand1 = new Operand(matches[1]);
@@ -48,6 +55,14 @@ app.set('expression', function() {
         return m;
     }
 
+    function createSingleOperandExpr(matches) {
+        var m = new app.models.BitwiseOperation();
+        m.operand1 = new Operand(matches[2]);
+        m.sign = matches[1];
+        m.string = matches.input;
+        return m;
+    }
+
     function createListOfNumbersExpression(input) {
         var operands = [];
         input.split(' ').forEach(function(n){
@@ -68,13 +83,14 @@ app.set('expression', function() {
         }
     }
 
+    function toHex(hex) {
+        return hex.indexOf('-') == 0 ? '-0x' + hex.substr(1) : '0x' + hex;
+    }
+
     function Operand(input) {
-        // console.log('input: ' + input);
         this.input = input;
         this.value = parseInt(input);
-        // console.log('value: ' + this.value);
-        var hex = this.value.toString(16);
-        this.hex = hex.indexOf('-') == 0 ? '-0x' + hex.substr(1) : '0x' + hex;
+        this.hex = toHex(this.value.toString(16));
         this.dec = this.value.toString(10);
         this.bin = (this.value>>>0).toString(2);
         this.kind = this.input.indexOf('0x') > -1 ? 'hex' : 'dec';
diff --git a/src/js/app/modelViews.js b/src/js/app/modelViews.js
index e0db390..82aac51 100644
--- a/src/js/app/modelViews.js
+++ b/src/js/app/modelViews.js
@@ -8,23 +8,41 @@ app.compose(function () {
     var cmdConfig = app.get('cmdConfig');
     var expression = app.get('expression');
 
-    app.modelView(app.models.BitwiseOperation, {
-        renderView: function(expr) {
-            var result = expression.createOperand(calc.calcExpression(expr), getResultMode([expr.operand1, expr.operand2]));
-            var maxLen = getBinaryLength([expr.operand1.value, expr.operand2.value, result.value]);
+    app.modelView(app.models.BitwiseOperation, function() {
+        function getTemplateId(model) {
+            switch (model.sign) {
+                case '<<':
+                case '>>':
+                case '>>>':
+                    return 'shiftExpressionView';
+                case '~':
+                    return 'notExpressionView';
+                default:
+                    return 'binaryExpressionView';
+            }
+        }
 
-            var model = Object.create(expr);
-            model.result = result;
-            model.operand1Binary = formatter.padLeft(expr.operand1.bin, maxLen);
-            model.operand2Binary = formatter.padLeft(expr.operand2.bin, maxLen);
-            model.resultBinary = formatter.padLeft(model.result.bin, maxLen);
+        return {
+            renderView: function(expr) {
 
-            var templateId = /<<|>>/.test(model.sign) ? 'shiftExpressionView' : 'binaryExpressionView';
-            var template = app.template(templateId);
+                var result = expression.createOperand(calc.calcExpression(expr), getResultMode([expr.operand1, expr.operand2]));
+                var maxLen = getBinaryLength([expr.operand1.value, expr.operand2 != null ? expr.operand2.value : 0, result.value]);
 
-            var el = template.render(model);
-            colorizeBits(el);
-            return el;
+                var model = Object.create(expr);
+                model.result = result;
+                model.operand1Binary = formatter.padLeft(expr.operand1.bin, maxLen);
+                if(expr.operand2) {
+                    model.operand2Binary = formatter.padLeft(expr.operand2.bin, maxLen);
+                }
+                model.resultBinary = formatter.padLeft(model.result.bin, maxLen);
+
+                var templateId = getTemplateId(model);
+                var template = app.template(templateId);
+
+                var el = template.render(model);
+                colorizeBits(el);
+                return el;
+            }
         }
     });
 
@@ -105,7 +123,7 @@ app.compose(function () {
 
     function getResultMode(operands) {
         for(var i=0; i<operands.length; i++) {
-            if(operands[i].kind == 'hex') {
+            if(operands[i] != null && operands[i].kind == 'hex') {
                 return 'hex';
             }
         }
diff --git a/tests/domain/expressionSpec.js b/tests/domain/expressionSpec.js
index fb28034..7dfb5d4 100644
--- a/tests/domain/expressionSpec.js
+++ b/tests/domain/expressionSpec.js
@@ -3,12 +3,11 @@ var expression = app.get('expression');
 
 describe("expression parse", function() {
 
-    var shouldParse = ['0x2>>1', '1 2 3', '0x1 1 2 3 5', '0x1>>0x2', '1|2'];
+    var shouldParse = ['0x2>>1', '1 2 3', '0x1 1 2 3 5', '0x1>>0x2', '1|2', '-9', '-1|-2', '~3'];
 
     it("should be able to parse", function() {
        shouldParse.forEach(function(expr) {
-           console.log(expr);
-           expect(expression.canParse(expr)).toBe(true);
+           expect(expression.canParse(expr)).toBe(true, 'expr: ' + expr);
        })
     });
 
@@ -19,7 +18,10 @@ describe("expression parse", function() {
         "0xf>>0xa": { operand1: 15, operand2:10, "sign":">>", string:"0xf>>0xa" },
         "0x10&0x11": { operand1: 0x10, operand2:0x11, "sign":"&", string:"0x10&0x11" },
         "0x1a^11": { operand1: 0x1a, operand2:11, "sign":"^", string:"0x1a^11" },
-        "0x1a>>>11": { operand1: 0x1a, operand2:11, "sign":">>>", string:"0x1a>>>11" }
+        "0x1a>>>11": { operand1: 0x1a, operand2:11, "sign":">>>", string:"0x1a>>>11" },
+        '~3': { operand1: 3, operand2: null, "sign":"~", string:"~3" },
+        '~0xa': { operand1: 0xa, operand2: null, "sign":"~", string:"~0xa" },
+        '~-0xa': { operand1: -0xa, operand2: null, "sign":"~", string:"~-0xa" }
     };
 
     it("should parse expressions", function() {
@@ -31,7 +33,14 @@ describe("expression parse", function() {
             expect(actual).not.toBe(null);
             expect(actual.sign).toBe(expected.sign);
             expect(actual.operand1.value).toBe(expected.operand1);
-            expect(actual.operand2.value).toBe(expected.operand2);
+            if(expected.operand2 != null) {
+                expect(actual.operand2.value).toBe(expected.operand2);
+            }
+            else
+            {
+                expect(actual.operand2).not.toBeDefined();
+            }
+
             expect(actual.string).toBe(expected.string);
         }
     });